Silicon - A tetravalent nonmetallic element; next to oxygen it is the most abundant element in the earth's crust; occurs in clay and felspander and granite and quartz and soft sand; used as a semiconducter in transistors.
Potassium - A soft, silver-white, highly or explosively reactive metallic element that occurs in nature only in compounds. It is obtained by electrolysis of its common hydroxide and found in, or converted to, a wide variety of salts used especially in fertilizers and soaps.
Zinc - A metallic chemical element, it has a white colour with a bluish tinge. It has a high resistance to atmospheric corrosion and a major use is as a protective coating for iron and steel sheet and wire.
Potassium - A soft, silver-white, highly or explosively reactive metallic element that occurs in nature only in compounds. It is obtained by electrolysis of its common hydroxide and found in, or converted to, a wide variety of salts used especially in fertilizers and soaps.
Zinc - A metallic chemical element, it has a white colour with a bluish tinge. It has a high resistance to atmospheric corrosion and a major use is as a protective coating for iron and steel sheet and wire.